docs: def save(self):
          """Save this config to disk.
  
          If the charm is using the :mod:`Services Framework <services.base>`
          or :meth:'@hook <Hooks.hook>' decorator, this
          is called automatically at the end of successful hook execution.
          Otherwise, it should be called directly by user code.
  
          To disable automatic saves, set ``implicit_save=False`` on this
          instance.
  
          """
          with open(self.path, 'w') as f:
              os.fchmod(f.fileno(), 0o600)
              json.dump(self, f)